Fluid pressure sealed garter strap for cylinder molds



Jan. 27, i953 HORNVBOSTEL 2,626,543

' FLUID PRESSURE SEALED GARTER STRAP FOR CYLINDER MOLDS Filed Oct. 27.1948 2 SHEETS-SHEET 1 In VE'nZar' Patented Jan. 27, 1953 FLUID PRESSURESEALED GARTER STRAP FOR CYLINDER MOLDS Lloyd Hornbostel, Beloit, Wis.,assignor to Beloit Iron Works, Beloit, Wis., a corporation of WisconsinApplication October 27, 1948, Serial No. 56,808

Claims.

the cylinder mold is partially immersed. The exterior of the cylindermold is evacuated and as the mold rotates, the pond liquid passesthrough -the foraminous surface of the mold and out through the circularend faces of the mold into drain boxes carried by the vat side walls. As

the liquid passes through the foraminous mold surface, a deposition ofpulp fibers is formed upon this surface as a web. The web is removedfrom the mold surface by means of a pick-up felt which is pressedagainst the mold surface by means of a couch roll.

The circular end faces of the cylinder mold are open to permit theevacuation of the center of the mold and also to permit the egress ofwhite water passing through the cylinder surface to deposit fibersthereon. A proper sealing of the end faces of the mold has been aproblem longstanding in the art and numerous expedients have beenproposed for effectively sealing these faces. However, in each instanceof the prior art, frictional losses during operation of the machine haveseriously hampered the effective sealing of the cylinder ends and it hasbecome necessary to frequently shut down the machine so thatthe sealingmeans may be replaced. This shutting down of the machine has, of course,re-

. sulted in a considerable loss of operating time and has hamperedefficient, economical operation of this type of paper machine.

The present invention now provides an improved type of sealing means inwhich fluid pressure is employed to maintain a sealing ring in cylindermold mounted therein. This arcuate mounting block is provided with aconcentric groove in which the sealing ring is slidably mounted. Anexpansible tube connected to a suitable source of fluid, such as air,under pressure is bottomed in the groove to urge the sealing ring intocontact with the circular end faces of the cylinder mold. Upon wear ofthe sealing ring, the tube is expanded by fluid pressureto maintain thesealing ring in contact with the end faces of the mold even though thesealing ring may be eroded by frictional losses caused durin rotation ofthe mold.

' It is, therefore, an important object of the present invention toprovide an improved type of seal for a cylinder mold of a cylinder typepaper machine, the sealing means being actuated by fluid pressure tomaintain liquid-tight sealing contact-with the circular end faces of thecylinder mold despite frictional wear of the sealing means itself.

Another important object of the present invention is to provide animproved seal for cylinder-type paper making machines in which a sealingring is urged into contact with the circular end faces of a rotatablecylinder mold by means of fluid pressure. a

A still further important object of the present invention is to providean improved seal for a cylinder-type paper making machine comprising amounting block adapted to be secured to the interior side wall surfacesof a cylinder paper making machine, the mounting block being procontactwith the circular end faces of the cyl- M interior. side walls of acylinder machine vat in 'a position adjacent the circular end faces ofthe vided with a groove concentric with a cylinder mold disposed withinthe vat, and a sealing ring disposed in the groove and urged toward thecylinder mold by fluid pressure, the seal ring being maintained incontact with the cylinder mold by fluid pressure despite frictional wearof the ring duringoperation of the machine.

Other and further important objects of this invention will be apparentfrom the disclosures in the specification and the accompanying drawmgs.

On the drawings:

Figure 1 is a vertical sectional view, with parts shown in elevation, ofa cylinder-type paper making machine with the improved sealing means ofthe present invention;

Figure 2 is a fragmentary, enlarged elevational view of a side wall of apaper making machine having the cylinder mold removed and equipped withimproved sealing mean of the present invention;

Figure 3 is an enlarged, fragmentary, cross-sectional view similar toFigure 1 illustrating in greater detail a portion of the sealing meansof the present invention; and

Figure 4 is a fragmentary, enlarged, elevational view of a portion ofthe improved sealing means of the present invention.

A shown on the drawings:

In Figure 1, reference numeral l refers generally to a cylinder-typepaper making machine including a vat ll defined by side walls l2, endwalls l3 and a bottom closure wall M. A cylinder mold I5 is rotatablymounted within the vat H on shaft I6 extending axially through the moldI5 and packing rings I! carried by side Walls l2 into suitable journalboxes I3 adjacent each side wall l2. Shaft I6 is connected to a suitablesource of power (not shown) for rotating cylinder mold l5 within vat II.Each side wall 12 of vat H carries a drain box IQ for receiving thedrainage from the interior of cylinder mold l5 and an outlet 23 forconnection to an eductor fan for evacuating the interior of cylindermold I5.

Cylinder mold I5 is provided with a foraminous or wire screen coveredsurface 2! supported by spiders 22 having radial arms 23 connected tothe shaft [6. The end spiders 22 carry annular wear rings 24 removablysecured thereto, as by recessed screws 25.

Adjacent each end of the cylinder mold l5, the vat side walls 12 areprovided with an open topped slot 26 extending downwardly from the topof the vat and terminating in a rounded bottom 26a at a level above thedrain boxes NJ, as best shown in Figure 2. A removable wall portion 2!is mounted on each side wall l2 to cover the slot 26. The removable wallportion 21, fitting snugly within the slot 26, includes outlet andcarries packing ring H, receiving shaft I6 therethrough. The upperportion Zia of removable wall 2? extends above the side walls !2 andcarrie at its upper end an arcuate ring segment 28 secured to portion21a by suitable fastening means, such as bolts or screws 29. The arcuatesegment 23 is concentric with cylinder mold l5 and carries an integralflange 33 (Figure 1) extending inwardly from side walls 52 toward thecylinder mold l5. This flange 33 aids in supporting the parallel edgesof a conventional pick-up felt (not shown) contacting the mold 15.

As shown in Figure 1, 2 and 3, a fragmental ring or arcuate mountingblock 3! is secured to the interior surface of each vat side wall [2 bysuitable means, as by screws 32. Mounting block 3| is concentric withand of slightly smaller radius than cylinder mold Ill.

The mounting block 3| is provided with an arcuate groove 33 concentricwith the block 3! and opening toward cylinder mold I5. The bottom 33a ofgroove 33 is generally rounded for a purpose to be hereinafter morefully described.

An arcuate seal ring 34 of substantially rectangular cross-section isslidably retained in groove 33, the ring extending beyond the terminaledge of block 3| for contacting the ring 24 of cylinder mold 15 as bestshown in Figure 3. An inflatable tube 35, formed of rubber, plastic, orother suitable non-porous flexible, expansible material, is mounted inthe groove 33 and seated on the curved bottom 33a behind the seal ring34.

The tube 35 is connected by means of elbow 36 to a suitable source offluid, such a air, water and the like under pressure. As best shown inFigure 4, elbow 36 abuts closure plate 3'! secured to the fiat endsurface 38a of enlarged terminal portion 38 of mounting block 3|. Oneend of the elbow 36 receives a nipple 39 extending into tube 35 andsecured therein by means of wire or other suitable flexible fasteningmaterial wrapped about the surface of tube 35. A pipe or hose 4|attached to the other end of elbow 36 is connected to a suitable sourceof fluid under pressure as hereinbefore described.

The other end of tube 35, opposite that end secured to elbow 36, isclosed, as shown in Figure 2, by means of closure plate 42 similar toplate 31 and carrying a second nipple extending into tube 35 and securedthereto by means as hereinbefore described.

As shown in dotted outline in Figure 3, the noninflated tube 35 may beof generally circular cross-section. However, upon inflation of thetube, the tube become deformed as shown in Figure 3 to bear uniformlyagainst sealing ring 33 to urge the sealing ring into sealing contactwith the wear ring 24 of the cylinder mold I5. As the seal ring becomesworn by friction during rotation of the cylinder 15, the inflated tube35 expands to urge the seal ring into close fitting sealing engagementwith th wear ring 24. Thus, a positive seal is provided between thecylinder mold I5 and the vat walls I2 by the present invention and thisseal is not broken by wear of the seal ring.

It will, of course, be understood that various details of constructionmay be varied through a wide range without departing from the principlesof this invention and it is, therefore, not the purpose to limit thepatent granted hereon otherwise than necessitated by the scope of theappended claims.

I claim as my invention:

1. A seal adapted for the end face of a paper making machine cylindermold rotatably mounted in a vat, comprising an arcuate mounting blockfor attachment to an interior wall of said vat adjacent a mold end faceto oppose the mold end face in concentric relation therewith, an arcuateround-bottomed groove formed in said block, a resilient sealing strip ofrectangular cross-section slidably mounted in said groove, and anexpansible tube originally of circular cross-section adapted to beconnected to a source of fluid under pressure and snugly bottomed insaid groove for urging said strip into contact with said mold end face,said tube being partially deformed from its original circular crosssection by its fluid pressure contact with said sealing strip and theexpansion of said tube under pressure maintaining said strip in contactwith said mold cylinder by sliding movement of said strip in said groovedespite wear of the strip whereby the fluid pressure in said tube isuniformly applied via said strip throughout the contact area betweensaid strip and said mold end ace.

2. A seal adapted for sealing the circular end face of a paper makingmachine cylinder mold rotatably mounted in a vat, comprising a mountingblock adapted for mounting on a wall of said vat adjacent said mold,said block having an arcuate groove therein with an arcuate closed endand an open end for facing said circular end of said mold in concentricrelation therewith, a resilient sealing strip slidably mounted in saidgroove, and expansible means in extended surface engagement with saidstrip and snugly bottomed against the arcuate closed end of said groove,said means being connected to a source of fluid under pressure forurging said sealing ring into contact with said mold whereby the fluidpressure in said expansible means is uniformly applied via said stripthroughout the contact area between said sealing strip and said mold endface.

3. A seal adapted for sealing an open end face of a cylindrical moldrotatably mounted in a vat, comprising an annular wear ring adapted fordetachable mounting on a circular end face of said mold, an arcuatemounting block adapted for attachment to an interior wall of said vatadjacent said mold end face, said block having an arcuate round-bottomedgroove for concentric alignment with said mold end face, a resilientsealing strip slidably mounted in said groove and an expansible tube oforiginally circular cross-section connected to a source of fluid underpressure and bottomed in said groove in conforming contact with thebottom thereof behind said strip in extended contact therewiththroughout the length of said groove for urging said strip into contactwith said wear ring, the expansion of said tube under fluid pressureserving to maintain said strip in contact with said ring by slidingmovement of said strip in said groove despite wear of said strip wherebythe fluid pressure in said tube is uniformly applied via said stripthroughout the contact area between said strip and said Wear ring.

4. In a cylinder-type paper making machine having a cylinder moldrotatably disposed in a vat containing a pulp suspension, a sealdisposed between the end faces of said mold and the adjacent side wallsof said vat, comprising an arcuate mounting block for attachment to saidvat side walls, said block having an arcuate roove formed therein, saidgroove having an arcuate bottom and an open end facing toward said mold,a resilient sealing strip of rectangular cross-section slidably mountedin said groove and extending therebeyond, and expansible means bottomedin said groove and contacting said strip throughout substantially theentire length thereof, said expansible means being in conforming arcuatecontact with the bottom of said groove and in conforming plain contactwith the inner face of said strip for urging said strip into resilientsealing engagement with the adjacent end face of said mold whereby thefluid pressure in said expansible means is applied uniformly via saidstrip throughout the contact area between said sealing strip and saidmold end face.

5. A cylinder-type paper making machine comprising an open topped vathaving opposed side walls, a cylinder mold rotatably disposed in saidvat and having annular end faces in closely spaced relation to the innerfaces of said side walls of said vat, an arcuate mounting block securedto the inner face of each of the side walls of said vat and having anarcuate round-bottomed groove therein opening inwardly toward theadjacent end face of said mold, an expansible tube originally ofcircular cross-section mounted in each of said grooves in conformingextended surface contact with the bottoms thereof and adapted to beconnected to a source of fluid under pressure, and a resilient arcuatesealing strip of rectangular cross-section slidably received by each ofsaid grooves and bottomed against said tube in surface engagement withsubstantially the entire length thereof, those portions of said tubescontacting said strips being deformed from their original circularcross-section into conformity with the adjacent side of said sealingstrips and those portions of said tubes bottomed in said groovesretaining its original arcuate configuration, said strips being adaptedto extend beyond said blocks into surface engagement with said mold endfaces in sealing engagement therewith under fluid pressures exertedthereon by said expansible tubes with said fluid pressures and slidingmovement of said tubes in said grooves maintaining said strips insliding engagement with said end faces despite wear of said strips.

LLOYD HORNBOSTEL.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,166,882 Beaumont Jan. 4, 19161,800,149 Miller et a1. Apr. '7, 1931 2,312,519 Berry Mar. 2, 1943FOREIGN PATENTS Number Country Date 26,049 Great Britain Nov. 10, 1909421,020 France Feb. 13, 1911 248,021 Germany June 14, 1912 543,260Germany Feb. 3, 1932 656.453 Germany Feb. 7, 1938

